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Kuznetsnov, G. U., & Matyushkin, E. N. (1980). The snow leopard hunts. Int.Ped.Book of Snow Leopards, 11, 44–48.
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Wolf, M., & Ale, S. (2009). Signs at the Top: Habitat Features Influencing Snow Leopard Uncia Uncia Activity in Sagarmatha National Park, Nepal. Journal of Mammalogy, 90(3), 604–611.
Abstract: We used logistic regression to examine factors that affected the spatial distribution of sign (scrapes, feces, footprints, spray or scent marks, and rubbing sites) in a newly reestablished population of snow leopards (Uncia uncia) in Sagarmatha (Mount Everest) National Park, Nepal. Our results indicate that terrain and human activity were the most important factors determining the spatial distribution of leopard activity, whereas presence of their major prey species (Himalayan tahr [Hemitragus jemlahicus]) had only a moderate effect. This suggests that localities at which these animals are active represent a trade-off between suitable habitat and avoidance of potential risk from anthropogenic origins. However, the influence of prey presence was likely underestimated because of the methodology used, and likely weighed in the trade-off as well.
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Jackson, R. M. (1996). Home Range, Movements and Habitat use of Snow Leopard (Uncia uncia) in Nepal. Ph.D. thesis, University of London, University of London.
Abstract: Home ranges for five radio-tagged snow leopards (Uncia uncia) inhabiting prime habitat in Nepal Himalaya varied in size from 11-37 km2. These solitary felids were crepuscular in activity, and although highly mobile, nearly 90% of all consecutive day movements involved a straight line distance of 2km or less. No seasonal difference in daily movement or home range boundry was detected. While home ranges overlapped substancially, use of common core spaces was temporally seperated, with tagged animals being located 1.9 km or more apart during the smae day. Spatial analysis indicated that 47-55% of use occured within only 6-15% of total home area. The snow leopards shared a common core use area, which was located at a major stream confuence in an area where topography, habitat and prey abundance appeared to be more favorable. A young female used her core area least, a female with two cubs to the greatest extent. the core area was marked significantly more with scrapes, Faeces and other sighn than non-core sites, suggesting that social marking plays an important role in spacing individuals. Snow leopards showed a strong preference for bedding in steep, rocky or broken terrain, on or close to a natural vegetation or landform edge. linear landform features, such as a cliff or major ridgeline, were preferred for travelling and day time resting. This behavior would tend to place a snow leopard close to its preferred prey, blue sheep (Psuedois nayaur), which uses the same habitat at night. Marking was concetrated along commonly travelled routes, particularly river bluffs, cliff ledges and well defined ridgelines bordering stream confluences--features that were most abundant within the core area. Such marking may facilitate mutual avoidance, help maintain the species' solitary social structure, and also enable a relatively high density of snow leopard, especially within high-quality habitat.
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Sunquist, F. (1997). Where cats and herders mix. (snow leopards in Tibet and Mongolia). International Wildlife, 27(1), 27–33.
Abstract: The snow leopard inhabits a huge range of territory which encompasses some of Central Asia's most bleak and inhospitable terrains. The animal herders in these regions are desperately poor and yet they have agreed to cooperate with conservation groups in protecting the snow leopard. The World Wildlife Foundation has worked to create a refuge on the Pakistan-China border. Sheep herders near Askole, a village in the Baltistan region of northern Paksitan, drive their flocks past stone enclosures. The area is also home to snow leopards. With their natural prey dminished, leopards in 13 countries of central Asia occasionally feed on livestock, putting the cats on a collision course with mountain peoples.
Keywords: Mongolia; Tibet; herder; livestock; snow-leopard; predator; prey; World-Wildlife-Foundation; habitat; reserve; park; refuge; Pakistan; China; herders; parks; protected-area; snow leopard; browse; Wwf; world wildlife foundation; 1110; snow; leopard; range; territory; central; Central Asia; asia; Animal; region; conservation; wildlife; foundation; border; sheep; Baltistan; enclosures; area; home; snow leopards; snow-leopards; leopards; countries; country; Feed; Cats; cat; mountain; peoples; people
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Ale, S., & Whelan, C. (2008). Reappraisal of the role of big, fierce predators.
Abstract: The suggestion in the early 20th century that top predators were a necessary component of ecosystems because they hold herbivore populations in check and promote biodiversity was at Wrst accepted and then largely rejected. With the advent of Evolutionary Ecology and a more full appreciation of direct and indirect effects of top predators, this role of top predators is again gaining acceptance. The previous views were predicated upon lethal effects of predators but largely overlooked their non-lethal effects. We suggest that
conceptual advances coupled with an increased use of experiments have convincingly demonstrated that prey experience costs that transcend the obvious cost of death. Prey species use adaptive behaviours to avoid predators, and these behaviours are not cost-free. With predation risk, prey species greatly restrict their use of available habitats and consumption of available food resources. Effects of top predators consequently cascade down to the trophic levels below them. Top predators, the biggies, are thus both the targets of and the means for conservation at the landscape scale. |
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Ale, S., & Brown, J. (2007). The contingencies of group size and vigilance (Vol. 9).
Abstract: Background: Predation risk declines non-linearly with one's own vigilance and the vigilance of others in the group (the 'many-eyes' effect). Furthermore, as group size increases, the individual's risk of predation may decline through dilution with more potential victims, but may increase if larger groups attract more predators. These are known, respectively, as the dilution effect and the attraction effect.
Assumptions: Feeding animals use vigilance to trade-off food and safety. Net feeding rate declines linearly with vigilance. Question: How do the many-eyes, dilution, and attraction effects interact to influence the relationship between group size and vigilance behaviour? Mathematical methods: We use game theory and the fitness-generating function to determine the ESS level of vigilance of an individual within a group. Predictions: Vigilance decreases with group size as a consequence of the many-eyes and dilution effects but increases with group size as a consequence of the attraction effect, when they act independent of each other. Their synergetic effects on vigilance depend upon the relative strengths of each and their interactions. Regardless, the influence of other factors on vigilance – such as encounter rate with predators, predator lethality, marginal value of energy, and value of vigilance – decline with group size. Keywords: attraction effect,contingency,dilution effect,fitness,group-size effect,many-eyes effect,predation risk,vigilance behaviour; predation; decline; potential; predators; predator; feeding; Animals; Animal; use; food; effects; Relationship; behaviour; methods; game; Interactions; interaction; factor; value; Energy
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Johnsingh, A. J. T. (1983). Large Mammalian predator-prey in Bandipur. J.Bombay Nat.Hist.Soc., 80.
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McCarthy, K., Fuller, T., Ming, M., McCarthy, T., Waits, L., & Jumabaev, K. (2008). Assessing Estimators of Snow Leopard Abundance (Vol. 72).
Abstract: The secretive nature of snow leopards (Uncia uncia) makes them difficult to monitor, yet conservation efforts require accurate and precise methods to estimate abundance. We assessed accuracy of Snow Leopard Information Management System (SLIMS) sign surveys by comparing them with 4 methods for estimating snow leopard abundance: predator:prey biomass ratios, capture-recapture density estimation, photo-capture rate, and individual identification through genetic analysis. We recorded snow leopard sign during standardized surveys in the SaryChat Zapovednik, the Jangart hunting reserve, and the Tomur Strictly Protected Area, in the Tien Shan Mountains of Kyrgyzstan and China. During June-December 2005, adjusted sign averaged 46.3 (SaryChat), 94.6 (Jangart), and 150.8 (Tomur) occurrences/km. We used
counts of ibex (Capra ibex) and argali (Ovis ammon) to estimate available prey biomass and subsequent potential snow leopard densities of 8.7 (SaryChat), 1.0 (Jangart), and 1.1 (Tomur) snow leopards/100 km2. Photo capture-recapture density estimates were 0.15 (n = 1 identified individual/1 photo), 0.87 (n = 4/13), and 0.74 (n = 5/6) individuals/100 km2 in SaryChat, Jangart, and Tomur, respectively. Photo-capture rates (photos/100 trap-nights) were 0.09 (SaryChat), 0.93 (Jangart), and 2.37 (Tomur). Genetic analysis of snow leopard fecal samples provided minimum population sizes of 3 (SaryChat), 5 (Jangart), and 9 (Tomur) snow leopards. These results suggest SLIMS sign surveys may be affected by observer bias and environmental variance. However, when such bias and variation are accounted for, sign surveys indicate relative abundances similar to photo rates and genetic individual identification results. Density or abundance estimates based on capture-recapture or ungulate biomass did not agree with other indices of abundance. Confidence in estimated densities, or even detection of significant changes in abundance of snow leopard, will require more effort and better documentation. |
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Ale, S. B., Brown, J.S. (2009). Prey behavior leads to predator: a case study of the Himalayan tahr and the snow leopard in Sagarmatha (Mt. Everest) National Park, Nepal. Israel Journal of Ecology & Evolution, 55(4), 315–327.
Abstract: Rare, elusive predators offer few sightings, hindering research with small sample sizes and lack of experimentation. While predators may be elusive, their prey are more readily observed. Prey respond to the presence of a predator, and these fear responses may have population- and community-level consequences. Anti-predator behaviors, such as vigilance, allow us to sidestep the difficulty of direct field studies of large predators by studying them indirectly. Here we used a behavioral indicator, the vigilance behavior of the Himalayan tahr, the snow leopard’s main local prey, to reveal the distribution and habitat use of snow leopards in the Mt. Everest region of Nepal. We combined techniques of conventional field biology with concepts of foraging theory to study prey behavior in order to obtain insights into the predator’s ecology. The Himalayan tahr’s vigilance behavior correlates with the distribution of snow leopard signs. Tahr actually led us to six sightings of snow leopards. We conclude that behavioral indicators provided by prey offer a valuable tool for studying and monitoring stealthy and rare carnivores.
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Ferretti, F., Lovari, S., Minder, I., Pellizzi, B. (2014). Recovery of the snow leopard in Sagarmatha (Mt.Everest) National Park: effects on main prey. European Journal of Wildlife Research, (60), 559–562.
Abstract: Consequences of predation may be particularly
heavy on small populations of herbivores, especially if they are threatened with extinction. Over the 2006–2010 period, we documented the effects of the spontaneous return of the endangered snow leopard on the population of the vulnerable Himalayan tahr. The study area was an area of central Himalaya where this cat disappeared c. 40 years before, because of persecution by man. Snow leopards occurred mainly in areas close to the core area of tahr distribution. Tahr was the staple (56.3 %) of snow leopards. After the arrival of this cat, tahr decreased by more than 2/3 from 2003 to 2010 (mainly through predation on kids). Subsequently, the density of snow leopards decreased by 60%from2007 to 2010. The main prey of snow leopards in Asia (bharal, marmots) were absent in our study area, forcing snow leopards to specialize on tahr. The restoration of a complete prey spectrum should be favoured through reintroductions, to conserve large carnivores and to reduce exploitation of small populations of herbivores, especially if threatened. |